Abstract:This paper examines the correlation between social, economic, geographic, and policy factors on plug-in electric vehicle adoption across U.S. states for the purpose of understanding: which factors are significantly correlated to variations in battery electric vehicle (BEV) and plug-in hybrid electric vehicle (PHEV) market shares, how those factors vary between BEV and PHEV markets, and how those factors compare with those identified as influential in driving early hybrid (HEV) markets. Our methodology includes a statistical analysis of new vehicle registration data from calendar year 2013 to test the relationship between PHEV and BEV market shares against statewide variables. Several of the factors that existing studies find to be important in earlier HEV markets are also correlated with 2013 PHEV or BEV market shares. We also find different sets of variables to be significantly correlated with PHEV and BEV market shares, respectively, which suggests that these markets are distinct. The differences between the factors that are correlated with PHEV and BEV market shares highlight the possibility that strategies for promoting the overall adoption of plug-in vehicles may not affect the two vehicle types equally. However, further analysis should be undertaken prior to developing policies and approaches based on these findings.